Not Gentoo related, but you guys are usually pretty knowledgable and helpful so I'd see if anyone has any ideas...

Basically I got home yesterday to find my pc had switched itself off, and wouldn't switch back on again. Turning the psu off and then on again fixed that and now it powers up, however it won't boot. The fans spin up and the lights come on, but nothing happpens after that - it doesn't even send a signal to the monitor. It wont turn off either - the only way to turn it off is to switch off the psu.

It's obviously some kind of hardware failure, but tracking it down is pretty difficult as I don't have any spare components to swap in. Has this ever happened to any of you? If so what caused it?

My suspicion is that it's the psu, but it's still powering the fans and lights so I'm not so sure. Is it possible for something in a psu to break so that it's now underpowered, and therefore unable to power everything properly?

If the stuff powers up but the computer doesn't boot, then it's unlikely to be the power supply -- mainboard is probably fried. I'd get a new one (or borrow a friend's) since they're relatively cheap, and then move onto replacing the RAM (usually the computer starts to boot then hangs if RAM is bad)._________________Personal overlay | Simple backup scheme

What you are describing aounds like what happened to a friend of mine recently. We tested the PSU by shorting the green? and black? wires and it seemed to work. After much fiddling around he bought a new PSU and then everything worked again.

Recently some problems were reported with electrolyte-capacitors from some company which were built onto many Mainboards from different manufacturers. These capacitors seem to be b0rked and they might blow after some time._________________Dort wo schwarzer Rauch aufsteigt, sich alsbald ein Fehler zeigt.www.paludis-sucks.org | www.gentoo.de | www.gentoo-ev.org | www.gentoo.org

Thanks for the suggestions, looks like I might have an expensive weekend ahead of me!

I was originally suspicious of the psu because it's the only cheap "no-name" part in the system and dodgy psus are pretty common.

However it does look as though it could be the mainboard, which would be annoying as it's only about 9 months old. The southbridge chip got extremely hot when I turned on the system which was a little worrying. It's a gigabyte GA-7VAXP rev 1.1. Don't know if that's one of the ones with dodgy capcitors or not, but it came out around the same time as the dodgy capacitor story did so it wouldn't be a suprise.

There was an article of the relevant boards in a german newsgroup. People who experienced blown capacitors should post their model there. Altough it's not longer maintained(?) this could be interesting:

as a simple test, unplug the PSU from the board and plug it back in. sometimes it trips on a surge. additionally try pulling out all the ram and just putting one stick in. some new boards won't even start if the ram is bad/in wrong.

unforutnately it does sound like a dead MB, but at least this is a way to make sure._________________DKP

There are 10 kinds of people in the world:
Those who understand binary and those who don't...

What you are describing aounds like what happened to a friend of mine recently. We tested the PSU by shorting the green? and black? wires and it seemed to work. After much fiddling around he bought a new PSU and then everything worked again.

That's what happened to me too: I was really scared my mobo had gone tits up (A7A266 here too! ) since while the comp. would not boot the mobo power led was on.
Simple test for the PSU: short the aforementioned cables and then measure each other colored cable with any black one: you should get readings from all of them in the values of 5, 3.3 and 12 V. In my case everything was b0rked but a single 5volt that was the one giving the led light.

If you don't find any troubles there, then it smells like a mobo... In any case, a PSU is the cheapest piece of all so you could even start by a simple buy and try method._________________Need to flame people LIVE on IRC? Join #gentoo-otw on freenode!

This happened to me once, a while back with a p2-300 (slot 1). It was 4 o'clock in the morning, i was drunk, and i wanted to check my email.My cable modem AND my server were both locked solid. Rebooting the modem worked, the server not so easy. I couldn't get a post or beep codes no matter what I pulled, though the fans came on. I decided to put it all back together after pulling everything out (to test) and I decided to try with just the CPU. I had forgotten to unplug the beast and everything powered on as soon as I plugged in the cpu - the fans started up!! It beeped strangely and sickly for a few seconds and then turned off. Out of curiousity, I turned it back on and got the beep codes! Plugged everything else back in and it all started working just fine. I DON'T RECOMMEND THIS TO ANYONE who even THINKS that their PC might not be broken. I would never do it again.

check with your power company. you can sometimes get them to replace what was broken due to a power surge. A power surge took out the fridge and my parents were able to get the power company to replace it. The trick is to get them to admit to a power surge in your area then they have to replace what got fried

this is speaking in terms of where I am from which is in British Columbia Canada. though it cant hurt trying